[BRLTTY] BRLTTY blocked on console while Orca is running on Wayland

[Elias Oltmanns]

Hi Samuel,

On 2025-12-20 at 01:00:18 (+0100), Samuel Thibault <samuel.thibault at ens-lyon.org> wrote:
> Hello,
> Elias Oltmanns, le ven. 19 déc. 2025 18:51:31 +0100, a ecrit:
>> On 2025-12-19 at 14:44:27 (+0100), Samuel Thibault <samuel.thibault at ens-lyon.org> wrote:
>> > Hello,
>> > Elias Oltmanns, le ven. 19 déc. 2025 14:32:14 +0100, a ecrit:
>> >> - Braille device responds to Orca now (as expected).
>> >> - Switch to tty2 in text mode.
>> >> - The braille device still shows Orcas output
>> > 
>> > It looks like orca doesn't manage to properly claim only the VT of the
>> > wayland session.
>> > 
>> > When running inside a terminal, do you have these environment variables
>> > set:
>> > 
>> > XDG_VTNR 
>> > WAYLAND_DISPLAY
>> > DISPLAY
>> > WINDOWPATH
[...]
>> When I launch „terminal“ from within my GNOME session, XDG_VTNR is not
>> set anymore,
> 
> Ok, so that's why.
> 
> Is your system using systemd? Normally it's set in the VT sessions.

Yes, systemd rules them all. Still, XDG_VTNR is not set when I start
terminal under Wayland.

By the way, after login on the text console on tty2, XDG_VTNR is set.
Once I attach to my tmux session (or start a new one), however, XDG_VTNR
is not set there either. Only when I detach, hence returning to tty2,
XDG_VTNR is set again.

>
>> > Please also post the content of
>> > 
>> > /proc/1234/environ
>> > 
>> > where you replace 1234 with the pid of orca, so we get to know what
>> > exactly orca has as environment variables.
>> 
>> This file appears to be empty since cat produces no output.
> 
> Had you replaced 1234 with the pid of orca? It's really not supposed to
> be empty.

Yes, I did replace it. Since then, I have started using the following
command for testing:

tr '\0' '\n' < /proc/`pidof orca`/environ

Strangely enough, this results in a lot of empty lines and nothing else.
That is to say:

$ tr '\0' '\n' < /proc/`pidof orca`/environ | wc -l
3143
$ tr '\0' '\n' < /proc/`pidof orca`/environ | grep -e "^." | wc -l
0

Then I tried the following:
$ tr '\0' '\n' < /proc/`pidof gnome-session-init-worker`/environ | grep XDG_VTNR
XDG_VTNR=1
$ tr '\0' '\n' < /proc/`pidof gnome-shell`/environ | grep XDG_VTNR

So, gnome-shell does not have XDG_VTNR in its environment either.

Finally, I installed Mate and managed to launch a session with startx.
Orca with braille support enabled seemed to be working as expected. In
particular, there was no undue interference with BRLTTY when switching
to a tty in text mode. So, I went ahead and executed in that text mode
tty the from above:
$ tr '\0' '\n' < /proc/`pidof orca`/environ
Again, this produced just a sequence of newlines and nothing else, just
like with GNOME and Wayland.

So, this leaves me at a loss right now. Orcas environment remains a
mystery regardless whether I am running Mate/X or GNOME/Wayland, but
only in the latter case I have trouble with braille support when
switching to other ttys.

Best,

Elias